Jeder Gegner schickt Karten oben von seiner Bibliothek ins Exil, bis er auf diese Weise Karten mit Gesamt-Manabetrag 5 oder mehr ins Exil geschickt hat. Bis zum Ende des Zuges kannst du auf diese Weise ins Exil geschickte Karten wirken, ohne ihre Manakosten zu bezahlen.
If a spell you cast has
in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
Since you are using an alternative cost to cast the spells, you can't pay any other alternative costs. You can, however, pay additional costs, such as kicker costs. If the card has any mandatory additional costs, you must pay those.
If a card in a library has
in its mana cost, X is 0 for the purpose of determining its mana value.